Aerodynamically controlled grapple assembly

ABSTRACT

An aerodynamically controlled grapple assembly includes a frame member secured to an associated load line and a streamlined body mounted to the frame member. The streamlined body includes a main lifting surface extending away from the body in a first direction and a vertical stabilizer extending away from the body in a second direction. A pair of grapple arms are movably connected to the frame member.

The instant application is a divisional application of U.S. applicationSer. No. 12/761,015 which was filed on Apr. 15, 2010 and is stillpending.

BACKGROUND

The present disclosure relates to midair retrieval technology. Morespecifically, it relates to an aerodynamically controlled grappleassembly (hereafter sometimes referred to as the Aero-Grapple) which canbe employed during midair retrieval operations.

Midair retrieval is a technique used to capture an object while it isstill airborne. The object to be retrieved is slowed by means of one ormore parachutes, and a specially equipped aircraft, more particularly ahelicopter, matches the object's trajectory and catches it in midair.Successful midair retrieval techniques require favorable atmosphericconditions, a successful execution of maneuvers to bring a grapplinghook mounted beneath the retrieving helicopter into the correctposition, and the correct operation of the retrieval helicopter itself.Helicopters are the optimal aircraft for these operations, due to theirVertical Takeoff and Landing (VTOL) capability.

It has been determined that for midair retrieval, the use of a parafoilis advantageous in comparison to a parachute, in order to more easilyengage the object to be retrieved. A parafoil has numerous advantagesover a non-gliding “round” parachute, all of which contribute to a fargreater margin of safety as compared with legacy midair retrievaltechniques. The forward glide of a parafoil enables a helicopter toapproach and engage the object to be retrieved with a lower separationvelocity than is possible with a round parachute. A parafoil does nothave a large low-pressure area above it. This allows the helicopter tofly directly over the parafoil without fear of an uncommanded descentinto the parafoil. If maneuvering to the same proximity were attemptedover a round parachute, the helicopter would experience a rapid onset of“settling with power” as a result of hovering in the entrained down-flowpresent above the round parachute, likely causing a midair collisionwith the round parachute. In addition, a parafoil generates a lower rateof descent for a given weight and provides a better sight picture forthe retrieving pilot.

The state of the art in midair retrieval is exemplified by U.S. Pat. No.6,824,102 dated Nov. 30, 2004. The subject matter of that patent isincorporated herein by reference in its entirety. One problem with theknown midair retrieval system is that the hook or grapple currentlyemployed is not aerodynamically configured. Therefore, it cannot becontrolled. Various forms of hooks and grapples are known, includinglatching and remotely activated types. However, the known grapple whichis suspended below a helicopter will swing in an uncontrolled pendularmotion. This motion can be damped through aggressive precision controlinputs by the pilot of the capture helicopter, but it greatly increasesthe time required to capture a parafoil-borne payload.

Control of the Aero-Grapple by a trained flight crew member residing inthe retrieval helicopter would be advantageous in order to allow theretrieval helicopter to more easily capture payloads carried by adescending parafoil, parachute, or the like. It would be desirable toimprove the safety and reliability of an in-flight grapple engagement.To this end, it would be desirable to utilize lifting surfaces withaerodynamic controls integrated with the remote grapple mechanism inorder to control the position of the Aero-Grapple independent ofhelicopter motion.

Accordingly, it has been considered desirable to develop a new andimproved aerodynamic retrieval assembly, or Aero-Grapple, which meetsthe above stated needs and overcomes the foregoing difficulties as wellas others, while providing better and more advantageous overall results.

SUMMARY OF THE DISCLOSURE

According to one embodiment of the present disclosure, anaerodynamically controlled grapple assembly secured as an external loadfrom an associated flying vehicle is provided. The grapple assemblycomprises a frame member secured to an associated load line suspendedfrom the associated vehicle and a streamlined body mounted to the framemember and encasing at least a portion of the frame member. The bodycomprises a vertical member and, spaced therefrom, a vertical stabilizerto help orient the body in flight. A grapple mechanism is mounted to theframe member in spaced relation to the vertical member.

According to another embodiment of the present disclosure, anaerodynamically controlled grapple assembly is provided. In thisembodiment, the aerodynamically controlled grapple assembly comprises aframe member secured to an associated load line and a streamlined bodymounted to the frame member. The streamlined body comprises a mainlifting surface extending away from the body in a first direction and atail extending away from the body in a second direction. A pair ofgrapple arms are movably connected to the frame member.

According to a further embodiment of the present disclosure, anaerodynamically controlled grapple assembly is provided. In accordancewith this embodiment of the disclosure, the aerodynamically controlledgrapple assembly comprises a frame member secured to an associated loadline and a streamlined body mounted to the frame member. The streamlinedbody comprises a vertical member extending from the body and a verticalstabilizer extending from the body in a spaced manner from the verticalmember. First and second control surfaces are mounted to the verticalmember and a third control surface is mounted to the verticalstabilizer. A grapple mechanism is mounted to the frame member alongwith a mechanism for actuating the grapple mechanism. Means, supportedby the frame member, are provided for activating the first, second andthird control surfaces. The means are controlled remotely by wirelesscommand.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention may take form in various components and arrangements ofcomponents. The drawings are for purposes of illustrating a preferredembodiment of the disclosure and are not to be construed as limitingsame. In the drawings:

FIG. 1 is a perspective view illustrating the capture of a descendingpayload, suspended from a parafoil, by an aerodynamically controlledgrapple assembly supported from an aircraft, according to one embodimentof the present disclosure;

FIG. 1A is an enlarged perspective view of the aerodynamicallycontrolled grapple assembly illustrated in FIG. 1;

FIG. 1B is a reduced rear perspective view of the aerodynamicallycontrolled grapple assembly illustrated in FIG. 1A;

FIG. 1C is an enlarged perspective view of a portion of theaerodynamically controlled grapple assembly of FIG. 1B;

FIG. 2 is an enlarged front elevational view of the aerodynamicallycontrolled grapple assembly of FIG. 1;

FIG. 3 is a side elevational view of the aerodynamically controlledgrapple assembly of FIG. 2;

FIG. 4 is a schematic cross sectional view of a portion of theaerodynamically controlled grapple assembly of FIG. 2; and,

FIG. 5 is a schematic perspective view of a frame of the aerodynamicallycontrolled grapple assembly without an aerodynamic body or shell mountedthereto.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to the Figures, wherein the showings are for purposes ofillustrating a preferred embodiment of the present disclosure only, andnot for purposes of limiting same, FIG. 1 illustrates a retrieval line10 trailing from a parafoil canopy 12 that is carrying a payload 14 viapayload risers 16. A drogue parachute 18 can be attached to the line 10to accentuate the line's rearward streaming, making it a more stabilizedand visible target. The drogue also contains a physical stopper thatsecures the payload when the stopper comes in contact with the closedgrapple arm during the midair retrieval. An aircraft 20, such as ahelicopter, employs a load line 30 supporting a aerodynamicallycontrolled grapple assembly (hereafter sometimes referred to as theAero-Grapple) 40 to retrieve the payload 14. After the Aero-Grapple 40captures the retrieval line 10, the helicopter 20 ascends while movingforward, until it is directly above the parafoil 12, and then veryslowly ascends until the payload weight is transferred from the parafoilto the helicopter 20 via the load line 10. The Aero-Grapple 40 isdesigned so that it can be more easily controlled by the Aero-Grappleoperator in the helicopter.

With reference now to FIG. 1A, the Aero-Grapple 40 is comprised of amain grapple body 42 which is aerodynamically shaped or torpedo-shapedor cigar-shaped, and could be termed a nacelle, as is evident from FIGS.1B, 2 and 3. Thus, the body 42 has rounded surfaces to decrease airresistance. Extending upwardly from the main grapple body 42 is avertical member or lifting surface 44. Extending aft from the maingrapple body 42 is a vertical stabilizer or tail 46 to stabilize andcontrol the heading of the Aero-Grapple when in forward motion. The tailincludes a control surface 48 (FIG. 3). Similarly, the vertical member44 includes control surfaces 50A and 50B (FIG. 1C) that are deployedappropriately to produce both lift and drag. These can be termed splitflaps. As is known, such flaps can be separated from each other into adeployed orientation, as shown in FIG. 1C, or brought together into analigned condition or stowed orientation, as shown in FIG. 1B. Each flapcan be separately actuated as will be discussed below, and can bedisplaced by about 10-15° from its stored position to its deployedposition. Positioned at the upper end of the vertical member 44 is aneye 55 (FIG. 1A) through which a lower end or second end 56 of the loadline 30 can be secured. As shown in FIG. 1, an upper end or first end 58of the load line 30 is secured to the helicopter 20, such as to anexternal load hook 59 (FIG. 5) of the helicopter.

Positioned on either side of the control surfaces 50A, 50B are wireguards 52A and 52B (FIG. 1C). The wire guards form cages around thecontrol surfaces 50A, 50B in order to prevent the load line 30 frombecoming entangled with the control surfaces 50A, 50B during the timewhen the flying vehicle 20 lifts the grapple 40 from the ground. Ifdesired, tabs 53 can be provided on the control surfaces 50A and 50B.These tabs serve to limit the deployed orientation of the split flaps.More particularly, when a tab 53 contacts the adjacent wire guard, itprevents the flap from rotating further away from its stowedorientation. In other words, it serves as a limit for the flaps deployedorientation. Of course, it should be recognized that such a means forlimiting the deployed orientation of the split flaps may not benecessary in all circumstances. Moreover, the means can take a varietyof other known forms as well.

The wire guards or cages also prevent the retrieval line 10 of theparafoil from getting hung up on or in a nook or cranny defined by thevertical member 44 and the control surfaces 50A, 50B during the processof retrieving or capturing a payload. The wire guards or wire cages canbe made of, for example, one-eighth inch diameter wire. It should berecognized that any suitable diameter of wire or shape of constructioncan be employed as well. It should also be appreciated that other knownshielding means for preventing hang up of the retrieval line 10 or theload line 30 with the vertical stabilizer 44 and the control surface 50could be employed as may be desired. A similar guard assembly 54 (FIG.1B) can be provided for the control surface 48 on the verticalstabilizer or tail 46, if so desired.

Located on the main grapple body 42 is a pair of grapple arms 60 and 62.The grapple arms are articulated so they can be moved from a deployedorientation (shown in solid lines in FIG. 2) to a retracted orientationof the grapple arms (shown in dashed lines), as illustrated by arrows 64and 66. The grapple arms are first positioned in the deployedorientation and are retracted either by the grapple operator or when theretrieval line 10 is identified by a sensor 65 (FIG. 5) installed in thegrapple mechanism that it is in position to be captured. With referencenow particularly to FIGS. 1B and 2, it can be seen that the grapple arms60 and 62 include planar lower surfaces 67 and generally planar uppersurfaces 68, but which each include an enlarged portion 69. Theretrieval line 10 is meant to be accommodated in the indented portiondefined in each of one of the grapple arms, trapped between surface 68of the arm and the lifting surface 44 when the grapple arm is actuatedto move to the retracted orientation.

With reference now to FIGS. 4 and 5, the Aero-Grapple includes astructural frame or strength member 70 which supports both the maingrapple body 42, and the vertical lifting surface 44. While a particulardesign of a structural frame 70 is illustrated in the embodiment of FIG.5, it should be appreciated that any suitable frame design can beemployed, depending on the precise shape of the Aero-Grapple 40 and theweight of the payload which is meant to be retrieved by theAero-Grapple. In the embodiment illustrated in FIG. 5, the structuralframe 70 comprises a lower portion 72 which can be approximatelyrectangular in shape and a tubular portion 74 extending upwardly fromthe rectangular portion 72. It should be appreciated that the tubularportion 74 can be housed in the main lifting surface 44. The somewhatrectangular portion 72 can be housed in both the aero body 42, as wellas the main lifting surface 44, as is apparent from FIG. 4. If desired,a somewhat larger diameter tubular section 76 can be provided at theintersection of the tubular member 74 and the rectangular member 72. Inthe embodiment shown, the upper end of the structural frame 70, moreparticularly, the tubular member 74, terminates in the eye 55.

Housed in the main grapple body 42 can be one or more ballast plates orweights 78. In the embodiment illustrated, the ballast plates 78 aresecured to the lower portion 72 of the structural frame 70. The numberof ballast plates 78 can be varied according to the intended airspeedand desired flight dynamics of the Aero-Grapple in order to obtain thedesired fore-aft grapple position in flight. Thus, the ballast platesare optional. It should be appreciated that the aero body 42 and themain lifting surface 44 are mounted to, and supported by, the structuralframe 70. If damage occurs to the aero body 42, the main lifting surface44 or the vertical stabilizer 46 during retrieval of a load, one or moreof these items can be replaced as needed. In other words, the aero bodyand its associated components serve as a shell around the structuralframe 70. They provide the streamlined shape and control surfaces whichare necessary in order to more accurately control the movement of theaerodynamic grapple assembly according to the present disclosure.

As is evident from FIG. 4, in the illustrated embodiment, a servoactuator 80 moves the control surface 48 on the vertical stabilizer ortail 48 via a shaft or linkage 82. Similarly, servo actuators 84 a and84 b move the control surfaces 50A and 50B via shafts or linkages 86 aand 86 b. The grapple arms 60 and 62 are moved via a hook actuator 90via one or more link members 92. As will be appreciated, the hook 62 isnot visible in FIG. 4. Controlling all of the servo actuators and thehook actuator is a helicopter crew member who is a trained Aero-Grapplesystem operator. Such control can be accomplished remotely by wirelesscommand via radio signals or other electronic signals. To this end, areceiver-decoder 100 is provided in the main grapple body 42. Thereceiver-decoder communicates with the various actuators via suitableelectrical lines, such as at 102.

The servo actuators actively control the angular deflection of thecontrol surfaces or split flaps 50A and 50B, as well as control surface48. In this way, the position of the Aero-Grapple can be changed inorder to suit the task of retrieving the payload 14 (FIG. 1). It shouldbe appreciated that the split flaps can be individually controlled asmay be necessary. That is the reason why separate actuators and linkagesare provided, one for each of the flaps. The grapple actuator 90 movesthe grapple arms 60 and 62 from the open to the closed position, or viceversa, via linkage 92.

It should be appreciated that the dynamic and aerodynamic requirementsfor stabilizing and controlling a non-lifting, towed body arefundamentally different from those which pertain to airplanes. Inairplanes, a lifting action of the airplane's wings is vertical. Incontrast, for the Aero-Grapple illustrated in the embodiment of FIGS.1-5, lift forces are used to control the Aero-Grapple's lateralposition. Hence, the vertical stabilizer or tail 46 is used fordirectional control, and the vertical lifting surface 44 produces liftin the horizontal direction in order to control the lateral position ofthe Aero-Grapple.

One embodiment of an Aero-Grapple according to the present disclosurehas been provided. In this embodiment, the Aero-Grapple is comprised ofa structural framework covered by an aerodynamic body. The body iscomprised of a vertical wing used to create lateral lift forces and avertical stabilizer or tail, which is used to control the direction offlight. The vertical wing or main lifting surface extends verticallyupward from the body and the vertical stabilizer or tail extendsdownward below the body, spaced aft from the lifting surface. Twocontrol surfaces, the split flaps, are mounted to the main liftingsurface. The vertical stabilizer has the third control surface mountedto it. A grapple mechanism is held by the body and provides for theopening and closing of the grapple arms. A means to activate the first,second and third control surfaces is located in the body. The means areactivated remotely by wireless command.

It should also be appreciated that the Aero-Grapple disclosed herein isuseful for a number of purposes, not just for midair retrieval withaircraft such as helicopters, engaging objects such as parafoils orparachutes. The subject matter of the disclosure herein can be employedmore generally for connecting any two vehicles in flight. For example,the aerodynamic body according to the instant disclosure can be employedeven without the aerodynamically controlled grapple assembly so that itcould be adapted for use more generally in connecting any two vehiclesin flight. To this end, the first vehicle can tow the aerodynamic bodyand the second vehicle can be provided with suitable means for capturingthe aerodynamic body thereby allowing the first and second vehicles tobe connected in flight. Such connection of the vehicles may be usefulfor refueling, or other purposes. In addition, a connection assemblyother than the hooks illustrated in FIGS. 1A-5 can be provided on theaerodynamic body and employed to connect the first vehicle to anotherobject in the air, when so desired.

The disclosure has been described with reference to a preferredembodiment. Obviously, modifications and alterations will occur toothers upon a reading and understanding of the preceding specification.It is intended that the invention be construed as including all suchmodifications and alterations insofar as they come within the scope ofthe appended claims or the equivalents thereof.

What is claimed is:
 1. An aerodynamically controlled grapple assemblysuspended as an external load from an associated flying vehicle,comprising: a frame member secured to an associated load line suspendedfrom the associated vehicle; a streamlined body mounted to said framemember and encasing at least a portion of said frame member, said bodycomprising a vertical lifting surface extending upwards from said bodyand, spaced therefrom, a vertical stabilizer extending rearwardly fromsaid body and at least one of said vertical lifting surface and saidvertical stabilizer being adapted to help orient said body in flight;and, a grapple mechanism mounted to said frame member in spaced relationto said vertical stabilizer.
 2. The aerodynamically controlled grappleassembly of claim 1 wherein said grapple mechanism is spaced from saidvertical lifting surface.
 3. The aerodynamically controlled grappleassembly of claim 1 wherein said streamlined body encloses all of saidframe member, except for a pair of grapples of said grapple mechanism.4. The aerodynamically controlled grapple assembly of claim 1 furthercomprising a ballast weight which is mounted to said frame member. 5.The aerodynamically controlled grapple assembly of claim 1 wherein saidstreamlined body includes a longitudinal axis and said verticalstabilizer is spaced along said longitudinal axis from said verticallifting surface.
 6. The aerodynamically controlled grapple assembly ofclaim 1 further comprising a support mounted to the frame member, viawhich the frame member can be suspended from the associated load line.7. The aerodynamically controlled grapple assembly of claim 1 whereinsaid grapple mechanism is moved via an actuating mechanism.
 8. Theaerodynamically controlled grapple assembly of claim 7 wherein saidactuating mechanism is activated remotely by wireless command.
 9. Theaerodynamically controlled grapple assembly of claim 1 wherein saidvertical stabilizer includes a control surface, said control surfacebeing moved by an actuator.
 10. The aerodynamically controlled grappleassembly of claim 9 further comprising a second guard protecting saidvertical stabilizer control surface.
 11. The aerodynamically controlledgrapple assembly of claim 1 wherein said grapple mechanism comprises apair of grapple arms that are articulated via an opening and closingactuator.
 12. The aerodynamically controlled grapple assembly of claim11 in which said actuator is activated remotely by wireless command. 13.The aerodynamically controlled grapple assembly of claim 1 wherein saidvertically oriented lifting surface comprises a pair of controlsurfaces.
 14. The aerodynamically controlled grapple assembly of claim13 further comprising a first guard protecting said pair of controlsurfaces.
 15. The aerodynamically controlled grapple assembly of claim13 wherein said pair of control surfaces comprise first and secondcontrol surfaces which can selectively deploy in opposite directions.16. The aerodynamically controlled grapple assembly of claim 15 whereinsaid first and second control surfaces are aligned in one orientation.17. The aerodynamically controlled grapple assembly of claim 13 furthercomprising first and second actuators for controlling a movement of saidpair of control surfaces.
 18. The aerodynamically controlled grappleassembly of claim 17 wherein said first and second actuators areindividually controlled.
 19. The aerodynamically controlled grappleassembly of claim 17 wherein said streamlined body further includes athird control surface mounted to said vertical stabilizer and a secondactuator for controlling a movement of said third control surface. 20.The aerodynamically controlled grapple assembly of claim 19 furthercomprising a remote control means for selectively operating said first,second and third actuators.